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INSTRUCTION MANUAL
for
Tripod Tower Sensor Mounting System
Model A76
DOCUMENT # 1286, Version G
1
Description
Sensor Exposure
The Tripod Tower and cross arm assemblies are
fabricated from galvanized steel tubing. The
Tripod Tower has adjustable mounting feet that
allow it to be mounted on a flat surface such as a
concrete pad or a pitched surface such as a roof
top. It is provided with a mast for attaching
wind sensors at a height of 10 feet or 3 meters.
Wind Speed
Mounting height:
Top of mast
Wind Direction
Mounting height:
Top of mast
Air Temperature
Mounting height:
Exposure:
4 - 5 feet (1 - 2 M)
North
Relative Humidity
Mounting height:
Exposure:
4 - 5 feet (1 - 2 M)
North
Orientation
The A76 Tripod tower should be oriented with
one side of the base parallel to the True North /
South Line. This will allow sensors attached to
cross arms to be provided a North or South
exposure as required.
Fuel Temperature
Mounting height:
Exposure:
10 - 12 inches
(25 - 30 cm)
South
Insolation
Mounting height:
Exposure:
4 - 5 feet ( 1 - 2 M)
South
Soil Temperature
Mounting Depth:
Soil Moisture
Mounting Depth:
4 - 20 inches
(10 - 50 cm)
4 - 20 inches
(10 - 50 cm)
Note: Locate soil moisture sensors at least 10
feet (3 meters) from any metallic object such as
tower leg or ground rod.
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Figure 1
Tower Orientation
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Figure 2
Tripod Mounting Dimensions
Figure 3
Cross Arm Clamp Detail
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Grounding
Mounting
A ground rod should be installed as close to the
tower as possible. It should be electrically
connected to the mast and tower legs with a
length of wire with as straight a run as possible.
The Tripod Tower can be attached to a wooden
roof using the screws provided. All penetrations
of the roof membrane must be sealed after
installation.
ESTABLISHING EARTH GROUND
If the tower is to be deployed at a remote site, a
concrete foundation 3 feet square ( 1 meter
square) and 6 inches deep (6.5 cm) should be
provided. Attach the tower using bolts preset in
the foundation. The spacing of the tower legs is
adjustable + 0.5 inch ( + 1.2 cm).
A copper-clad rod should be driven into the
ground eight feet or more. Since frozen soil is
a poor conductor of electricity, the ground rod
should extend three feet below the deepest frost
line for your area. If the latter is not feasible
because of rock formations or other problems,
contact the factory for advice.
Mast
Insert mast through frame at top of tower into
triangular bottom support. The “L” shaped
The type of soil influences the ability of the
ground rod to dissipate energy. Clay and loam bracket attached to the bottom support is to
prevent the mast from slipping down. It should
are best; sand or gravel poor. Ground rods
should be installed as vertically as possible since be positioned inside the mast tube.
surface soil generally has a lower conductivity
Tighten six screws supporting the mast.
than subsoil.
Lightning protectors should be attached to this
mast as close to their respective sensors as
possible.
Buried Cable
Close lightning strikes present special problems
for systems using buried cable. Energy dissipating from a lightning strike can result in earth
potentials of several thousand volts per meter.
For cable lengths over 5 meters, the potential
voltage difference from one end of the cable to
the other can easily exceed the insulation breakdown voltage. This can damage attached circuitry and the cable.
Pole Mounted A96 Surge Arrestor
To help avoid this problem AWG # 8 or larger
bare copper wire should be buried adjacent to the
signal cable and attached to earth ground at both
ends. Avoid sharp turns and coils in the bare
copper wire. The bare copper wire will conduct
the majority of the lightning-induced current and
keep the components tied to the signal cable at
nearly the same potential, thus preventing damage.
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A76-SD Support for Anemometer and Wind
Vane
A76-X5 Cross Arm
This cross arm is intended to support a variety of
sensors designed to couple with one inch electromechanical tubing. The A76-X5 Cross Arm
should be generally be aligned with the North /
South line to provide proper exposure for the
sensors. See Figure 1. Attach the cross arm to
the tower at a height of 4 - 5 feet ( 1.2 - 1.5 M)
using the stainless steel U bolt arrangement
shown in Figure 3. The U bolt plates should be
located on the inside of the tower leg to make the
cross arm as stiff as possible. Use a carpenter’s
level or other means to make the cross arm as
level as possible.
This assembly is designed to support the Model
A75-104 Three Cup Anemometer and A75-302
or A75-301 Wind Direction Vane.
1.
Attach the anemometer and wind vane to
the supporting 0.5 inch tube using the cotter
pins.
2.
Secure the sensors to the tube with a set
screw in their base.
3.
Note the orientation of the North arrow
of the wind vane.
4.
Slip the wind sensor assembly over the
supporting mast and align the wind vane to True
North.
A76-I Pyranometer Mount
This mount is designed to provide a mounting
base for the LI-200 Pyranometer.
5.
Tighten the set screw attaching the wind
sensor assembly to the mast in the tripod tower.
Install the mounting bracket for the pyranometer
on the South facing end of a cross arm with a
height of 4 - 5 feet (1.2 - 1.5 M). Adjust the base
to be as level as possible and tighten the set
screw. Remove three retaining nuts from the
retaining screws and slide the pyranometer onto
the base. Use the three adjusting legs on the
pyranometer base to level the base. Secure the
base with the three retaining nuts.
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A76-T Mount
A76-HT Mount
This mount is intended to support an air temperature sensor on the North facing end of a
cross arm or attached to a North facing wall.
This mount is intended to support an air temperature and relative humidity sensor on the
North facing end of a cross arm. The cross arm
should be at a height of 4-5 feet (1.2 - 1.5 M)
with a North / South orientation. It is provided
with a passive radiation shield for the A70-HT
Air Temperature and Humidity Sensor.
When used with the A76 Tripod Tower the cross
arm should be at a height of 4-5 feet (1.2 - 1.5
M) with a North / South orientation. It is provided with a passive radiation shield for the S93
Air Temperature. The assembly should be oriented so that it is not reached by direct sunlight.
The tube protecting the temperature sensor must
be mounted on a slope to allow any moisture
entering it a free drain path. Tighten the retaining
screw.
Install the A70-HT Temperature and Humidity
sensor in the radiation shield and slide the
assembly over the North end of the cross arm.
The sensor is protected by the screen cover
protruding from the side of the enclosure. The
assembly should be oriented so that it is not
reached by direct sunlight and is shielded from
precipitation. Tighten the retaining screw.
When wall mounted fasten the A76-T to a North
facing wall such that the tube protecting the
temperature is on a slope to allow any moisture
entering it a free drain path
Figure 4
A76-HT Mount & Radiation Shield
A76-T Mount
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LIMITED WARRANTY
RIGHTS WHICH VARY FROM STATE TO STATE.
SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LIMITATIONS ON HOW LONG
AN IMPLIED WARRANTY LASTS, SO THE ABOVE
LIMITATIONS AND/OR EXCLUSIONS MAY NOT
APPLY TO YOU. This warranty complies with the
Magnuson-Moss Consumer Warranty Act, and completely
replaces any warranty printed on promotional material
describing products of Comptus Inc.
.
COMPTUS Inc. extends this warranty to the original
consumer only. Any product manufactured by Comptus is
warranted against defect for a period of ONE YEAR
beginning on the date of purchase by the consumer or two
years beginning on the date of purchase from Comptus by
the authorized dealer, whichever expires sooner.
TO OBTAIN WARRANTY SERVICE, the purchaser must
contact Comptus and receive return authorization. Such
correspondence should be addressed to: Comptus Inc., 202
Tamarack Rd., Thornton, NH. 03285. All warranty service
is performed at the factory. All incidental expenses,
including shipment of products to Comptus by the purchaser, shall be the sole responsibility of the purchaser.
WARRANTY SERVICE is at the sole discretion of
Comptus and free of charge for parts and labor. Under the
above terms, Comptus will repair or replace the defective
component(s), provided that:
HOW TO RETURN EQUIPMENT
TO COMPTUS
1. Contact the Comptus Service department with the model
and serial number of the unit. Be prepared to provide the
symptoms of the problem as many are solved without the
need for returning the equipment. Have a person with
firsthand experience of the trouble on hand to provide
specific information.
2. Comptus will issue a Return Material Authorization
Number (RMA#) if required. This will ensure the fastest
response and least cost for all parties. Please reference this
number in all correspondence. This number should be
printed on the shipping container.
a) the product has not been subjected to abuse, neglect,
accident, alteration, improper installation or servicing, or
used in violation of instructions furnished by Comptus;
b) the product has not been repaired or altered by anyone
except Comptus or its authorized service agencies;
3. Include a description of the service desired with the
returned equipment. If the equipment is being returned for
repair, please include a description of the problem.
c) the serial number has not been defaced, removed, or
otherwise changed;
4. If the equipment is packaged in a plastic case, wrap it in
aluminum foil, or other conductive material. This will
protect it from static electricity, as well as prevent the
packing material from jamming mechanical parts, such as
switches. Otherwise, place the equipment in a plastic bag,
again to prevent contamination by packing material.
d) the damage has not been caused by acts of nature
including windstorm and hail beyond those specified as
within the range of operating conditions;
e) the damage has not been caused by shipping.
THIS WARRANTY IS IN PLACE OF ALL OBLIGATIONS OR LIABILITIES ON THE PART OF
COMPTUS FOR DAMAGES. IT DOES NOT APPLY
TO ANY COMPONENT OR EQUIPMENT RESOLD
BY COMPTUS IN ITS ORIGINAL CONDITION AS
RECEIVED BY COMPTUS FROM THE MANUFACTURER OR DISTRIBUTOR, AMONG THE DAMAGES EXCLUDED FROM THIS WARRANTY ARE
ANY INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF OR IN CONNECTION
WITH THE PRODUCT IN ANY WAY. Any implied
warranties are limited in duration to the duration of
the written warranty. No representative or person is
authorized to give any other warranty or assume for
Comptus any other liability in connection with the sale
of its products.
THIS WARRANTY GIVES YOU SPECIFIC LEGAL
RIGHTS, AND YOU MAY ALSO HAVE OTHER
Place the equipment in a suitable shipping container and
fill with packing material. There should be at least one inch
of packing material between the equipment and the
shipping container on all sides.
5. Equipment will be returned C.O.D. to sender if any
charges are incurred, unless other arrangements are made
in advance.
SHIP THE EQUIPMENT TO:
Comptus
202 Tamarack Rd.
Thornton NH 03285 U.S.A.
Telephone : 603 726-7500
Telfax
: 603 726-7502
e-mail
: service@comptus.com
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NOTE: Please be sure to include the RMA Number, as
described in Item 1, on the shipping container.
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Packing List
A76 Tripod Tower
Quantity
Description
1
6
1
6
5 foot Tower
5.6" Black Cable Ties
5 Foot Mast
Mounting Screws
A76-HT Cross Arm
1
1
4
4
Cross Arm
Radiation Shield
U bolts
5.6" Black Cable Ties
A76-I Cross Arm
1
1
4
4
Cross Arm
Pyranometer Support
U Bolts
5.6" Black Cable Ties
A76-SD Wind Sensor Mount
1
6
Sensor Mount
5.6" Black Cable Ties
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WWW.COMPTUS.COM Phone: 603 726-7500 Fax: 603 726-7502